Background/Purpose: Despite similar myocardial infarction risks in SLE and diabetes mellitus (DM) patients, individuals with SLE enrolled in Medicaid had substantially higher rates of coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) compared to age- and sex-matched DM patients. However, little is known about mortality after coronary revascularization procedures in SLE versus DM and general population patients and we hypothesized that SLE patients would have poorer outcomes. We evaluated 30-day mortality rates following coronary revascularization procedures among SLE compared to DM and general population patients enrolled in Medicaid.

Methods: We utilized Medicaid Analytic eXtract (MAX) data, containing billing claims from 29 most populated U.S. states (2007-2010) and identified adults aged ≥18-65 years with prevalent SLE or DM (≥3 ICD-9 codes, each ≥30 days apart) and >6 months enrollment prior to 3rd code, and patients without SLE or DM (“general population”). Among those in each cohort undergoing first CABG or PCI, we calculated post-procedure 30-day mortality rates (MRs) and mortality rate ratios (MRRs) per 1,000 person-years, with 95% confidence intervals (95% CIs) compared to the DM and general populations separately. We used multivariable logistic regression models, adjusting for age, sex, race/ethnicity and Charlson index, to calculate odds ratios (OR) and 95% CIs, for 30-day mortality post-coronary revascularization procedures in the SLE compared to the DM and general population cohorts separately.

Results: Among 40,212 SLE patients, we identified 608 (1.51%) coronary revascularization procedures; among 80,424 prevalent DM, we identified 1185 (1.47%), and among 160,848 general population patients, there were 628 (0.39%) over similar follow-up periods in each group (approximately 1.7 years). Demographics and deaths within 30 days are shown in Table. Mean age at procedure was youngest in SLE patients and proportion of Black patients was highest in SLE. SLE patients had the highest 30-day post-revascularization mortality rate (351.35 [95% CI 221.36-557.67]) per 1,000 person years of observation, compared to DM (MRR 1.67 [95%CI 1.25-2.21]) and the general population (MRR 1.85 [1.31-2.63]). After multivariable adjustment, the odds of death within 30 days of coronary revascularization procedure were doubled in SLE compared to DM (OR 2.13 [95%CI 1.09-4.13]); a similar but non-significant trend was seen for SLE compared to general population (OR 1.93 [95%CI 0.85-4.42]).

Conclusion: SLE patients had 1.7 times higher 30-day mortality rates post-coronary revascularization compared to DM and general population patients, despite being on average much younger at procedure. After adjusting for demographics and comorbid index, SLE patients were twice as likely to die within 30-days of coronary revascularization procedure as DM patients. Future studies accounting for healthcare utilization, the complexity and indications of the procedures performed, SLE and cardiac disease severity, and investigating causes of post-procedure deaths are required.

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ACR Meeting Abstracts - https://acrabstracts.org/abstract/mortality-rates-after-coronary-revascularization-procedures-among-systemic-lupus-erythematosus-compared-to-diabetes-mellitus-and-general-population-medicaid-patients/